An internal combustion engine in a vehicle typically includes an air induction system for providing air to the engine. It is desirable to design the air induction system to maximize air flow to the engine, while minimizing noise emitted therefrom. One method to maximize air flow to the engine is to increase the size of a main air inlet orifice, which controls the amount of air permitted to flow into the system. However, increasing the size of the main air inlet orifice typically increases induction noise which is generated as air is drawn into the engine.
Resonators of various types have been employed to reduce engine induction noise by reflecting sound waves generated by the engine 180 degrees out of phase. The combination of the sound waves generated by the engine with the out of phase sound waves results in a reduction or cancellation of the amplitude of the sound waves. Such resonators typically include a single, fixed volume chamber for dissipating the engine induction noise. Multiple resonators are frequently required to attenuate sound waves of different frequencies. The function of resonators as described herein is described in commonly owned U.S. patent application Ser. No. 11/521,934 hereby incorporated herein by reference in its entirety. While resonators have been effective at reducing induction noise, air induction systems including resonators tend to minimize air flow to the engine, adversely affecting engine performance.
It would be desirable to produce an air induction system including a resonator bypass valve for maximizing air flow to an engine and minimizing noise emitted therefrom.